It is studied that a polymerized film, e.g., a high-molecular thin film represented by a polyimide thin film, is used as an interlayer insulating film of an electronic product, e.g., a semiconductor integrated circuit device, or as a liquid crystal alignment film of a flat panel display, e.g., a liquid crystal display device.
The high-molecular thin film can be formed by a deposition polymerization method which vaporizes a source monomer dissolved in a solvent, deposits the vaporized source monomer on a surface of a target object and subjects the deposited source monomer to a polymerization reaction on the surface of the target object.
In the deposition polymerization method, a polymerized film can be formed using a film forming apparatus which is a semiconductor manufacturing apparatus. Thus, the polymerized film can be used not only as a passivation film of a semiconductor integrated circuit device but also as an interlayer insulating film in an internal structure of a semiconductor integrated circuit device.
In a case of using the polymerized film as an interlayer insulating film, the polymerized film is exposed to a machining process such as etching or the like. After the machining process, a process using a chemical, e.g., a cleaning process using a cleaning solution, is performed with respect to the polymerized film.
However, it was found that, if the process using a chemical, e.g., the cleaning process using a cleaning solution, is performed with respect to the polymerized film, there is posed a problem of deterioration of film quality (e.g., reduction of a film thickness) of the polymerized film, alteration of the polymerized film, or peeling of the polymerized film in the worst case. Presumably, this is because the polymerized film is damaged by the cleaning solution.